This invention relates to a manually actuated pump dispenser which provides for a predetermined number of pump strokes for dosage control prior to automatically resetting after the final stroke. The pump plunger of the dispenser is locked against actuation in a condition prior to the first stroke and following the final stroke.
More particularly the dispenser according to the invention has a freely rotatable control ring engaging the plunger for controlling the number of plunger strokes and thereby the dosage during an unlocked condition of the pump for each revolution of the control ring. The control ring is coupled to the plunger in a manner for releaseably locking the plunger against reciprocation. The control ring and the plunger must be relatively rotated to unlock the ring thereby rendering the dispenser child-resistant.
U.S. Pat. No. 5,335,823 discloses a discharge apparatus for media of a random type in which a discharge process is performed with one or more discharge actuating means. The dispenser is so constructed that it can be moved backwards and forwards in one or more motion cycles in manual manner between one or more starting positions and one or more end positions. In one or more of such positions the discharge actuating means can be fixed by one or more catch systems at least within certain movement limits against movements in the actuating direction, and/or return direction in the catch system can be released again by one or more manual actuations.
U.S. Pat. No. 4,565,302 discloses an actuatable dosing mechanism with an actuating pusher for dispensing a measured quantity of a flowable substance from a container. A counter is provided for automatically counting the actuated strokes, the counter being started up by the actuation of the actuating pusher. A locking device is provided for the actuating stroke which can be actuated as a function of the counter. The locking means is activated after a daily maximum dose of a certain number of strokes and can then be released again.
These prior art dosing mechanisms, however, generally lack the ability providing for a specified number of strokes for dosage control prior to being automatically reset after the final stroke. For example, the user may require three strokes of nasal medicant per nostril such that after the end of the third stroke the dispenser is rendered child proof until the operator restarts the device. The known prior art dispensers having a dosage or metering control are incapable of achieving a specified control of designated strokes.